Inversion of Fracture Parameters from Tiltmeter Measurements During Hydraulic Fracturing

Ground deformation measured by high sensitive tiltmeters had been successfully applied to inverse subsurface hydraulic fracture parameters, such as location, orientation, dip and volume, etc. The conventional inversion approach based on the gradient method has a relatively limited convergent region, and could trap into a local optimum when given a relatively rough initial guess. In this paper, a new inversion approach based on Simulated Annealing (SA) algorithm is proposed. A synthetic test shows that this new approach significantly enlarges the method’s convergent region, relieves the accuracy requirement on initial guesses, and does not need any prior fracture information to start with, so would be a better choice compared with gradient-based inversion method.